JP2003139296A - Fiber reinforced pressure vessel and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber reinforced pressure vessel being light in weight and preventing permeation of gas by manufacturing a liner having the rigidity required when winding resin-impregnated fibers. SOLUTION: As the liner for winding the resin-impregnated fibers, a core 1 provided with a mouthpiece part 13 and a boss part 14 and made of thin- walled metal and a composite liner made of synthetic resin 2 to reinforce the rigidity are used. A thickness of at least a barrel part 11 as the core made of thin-walled metal is 0.5 mm to 0.05 mm. One sides of the barrel part 11 and at least a dome part 12 are separately manufactured. The dome part is inserted into an inner side or an outer side of the barrel part and is joined with it or a ringlike wear plate is provided on the inner side to join the barrel parts mutually on it for assembly. Recessed and projecting parts appearing on a surface are made smooth by resin for reinforcement.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to liquefied petroleum gas (L
PG), combustion fuel gas such as compressed natural gas (CNG),
Alternatively, in a pressure vessel used to supply fuel gas for fuel cells such as hydrogen gas and methane gas, or breathing air for medical and disaster prevention, etc., liner is wrapped with glass fiber, carbon fiber or Kevlar fiber impregnated with synthetic resin and cured. TECHNICAL FIELD The present invention relates to a fiber reinforced pressure vessel and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional fuel gas for combustion such as liquefied petroleum gas (LPG) or compressed natural gas (CNG), a pressure vessel for hydrogen gas, or a pressure vessel used for supplying breathing air for medical treatment, disaster prevention, etc. Since it is made of steel, it is heavy in transportation and needs to be light in weight. Therefore, in order to reduce the weight,
Fiber reinforced pressure vessels have been developed.

The fiber-reinforced pressure vessel that has been developed so far is
Metal or plastic (eg Japanese Patent Publication No. 5-8866)
It was reinforced by winding glass fiber or carbon fiber impregnated with a resin which is cured by the treatment, using 5) as a liner. In the case of a metal liner, there is an advantage that there is no gas permeability, but in order to reduce the weight, there is a limit to the liner made of only metal, and even in the patents so far, the minimum thickness is 0.5 mm or more. No application has been filed (JP-A-9-4294). Therefore, in order to further reduce the weight, it was necessary to use a plastic liner, but the plastic liner has a problem of gas permeability due to long-term storage, and as a countermeasure for that, the outer surface of the plastic liner is Metallic plating or covering with thin metal (Japanese Patent Publication No. 5-8866)
5) was proposed. However, the method of plating a metal film on the outer surface of the resin liner cannot (1) have sufficient effects to prevent gas permeability over a long period of time because pinholes are easily formed in the metal film. (2) Since the structure of the film has little plasticity, there is a problem that the film easily peels off due to expansion and contraction of the liner due to repeated high pressure when gas is filled and normal pressure when gas is released. Even if it is covered with thin metal, there are many gaps, and it is essentially difficult to prevent gas permeability.

[0004]

SUMMARY OF THE INVENTION In the prior art,
If the metal liner is made thinner to reduce the weight, it will not only be deformed with a large liner, but also with a small liner, it will be deformed due to lack of rigidity when winding the fiber, making it difficult to wind evenly with a smooth fit. There is a problem in that it is difficult to apply or that a non-uniform stress distribution is created after winding.

An object of the present invention is to provide a fiber-reinforced pressure vessel using a lightweight liner for wrapping resin-impregnated fibers, which has no gas permeability and rigidity, and a method for producing the same.

[0006]

In order to achieve the above object, in the fiber-reinforced pressure vessel and the method for producing the same according to the present invention, as a liner around which a resin-impregnated fiber is wound, a thin metal core and a reinforcing material are used. A composite liner made of synthetic resin is used. At that time, the thickness of the metal core is at least 1 mm or less, preferably 0.5 m.
The thickness was thin from m to 0.05 mm. Thereby, the gas permeability is achieved by the thin metal, and the rigidity of the liner is achieved by the reinforcing resin.

A trial calculation will be made for the weight reduction only in the body portion. By the way, when a 3 mm thick liner is made of aluminum alloy (density 2.69 g / cm3), it is 0.807.
It becomes g / cm2. On the other hand, when a composite liner of metal and resin is made of stainless steel (density 7.8 g / cm3) and resin (density 1.2 g / cm3), 3 mm
The thickness equivalent to the aluminum metal of thickness is
The stainless steel has a thickness of 0.66 mm and the resin has a thickness of 2.
It is 34 mm. That is, the thickness of stainless steel is 0.6
If the thickness is less than 6 mm, a lighter liner having a stainless steel-resin configuration can be produced, even if the same liner having a thickness of 3 mm is produced entirely from aluminum.

If the liner is made of a composite liner of metal and resin instead of the magnesia alloy (density of 1.74 g / cm3), which has the lowest density among metals, it is equivalent to the weight of magnesium having a thickness of 3 mm. The thickness is 0.23 mm for stainless steel and 2.7 for resin.
It will be 7 mm. If the composite liner is made of aluminum and resin, the weight of aluminum equivalent to magnesium having a thickness of 3 mm is 1.05 mm, and the thickness of the resin is 1.95 mm. That is, if the thickness of the metal is 0.23 mm or less for stainless steel and 1.05 mm or less for aluminum, the weight is lighter than that of a liner having a thickness of 3 mm made of a magnesium alloy.

In the above consideration, aluminum and stainless steel were used as the thickness of the core metal of the liner, but carbon steel or copper wrought can also be used. In other words, if the thickness of the body is about 1 mm or less for aluminum and about 0.5 mm or less for steel, stainless steel, and copper wrought, it is possible to reduce the weight as compared with the case where the liner is made of only lightweight metal.

On the other hand, the standard plate thickness according to the JIS standard is 0.35 mm or more for cold rolled steel plates, 0.3 mm or more for cold rolled stainless steel plates, and 0.3 mm for aluminum and aluminum alloy plates when thin. As described above, the thickness of phosphor bronze and nickel-white plate is 0.1 mm or more. Regarding the thickness of the plate that becomes the core of the liner, it is not limited to the thickness of the above JIS standard, and as thinner ones, those used in food cans and beverage cans,
There is also a thin wall with a thickness of 0.25 mm to 0.1 mm or less.
From these, it is considered that the thickness of the body portion of the liner core can be used up to at least 0.05 mm.

As a method of manufacturing the core of such a liner, basically, the core of the liner is manufactured by dividing it into at least two parts and then joining them. First, the first is the body, the second is the dome, and the dome is required at both ends of the body, but one dome may be integrally molded with the body. Also,
A boss portion is provided at the apex of the dome portions on both sides, and one of the boss portions is a mouthpiece for introducing gas. The caps may be provided on the dome portions on both sides, or only one may be provided, but in the case of only one, it is desirable to use a blind boss for the other because of the convenience of winding the resin-impregnated fiber later.

The liner core made of the above thin metal is wound with resin-impregnated fibers by a filament winding method or a resin-impregnated cloth tape is wound by a tape winding method for reinforcement. The method can produce a higher quality pressure vessel. In the case of the filament winding method, since the fibers are tensioned to be wound closely, the liner needs to have rigidity. Particularly when wound diagonally, when the liner is distorted, the fiber slips and cannot be wound evenly. Therefore, the inside or outside of the thin metal core of the liner is a thermosetting resin, that is, a rigid resin such as epoxy resin, unsaturated polyester resin, phenol resin, diallyl phthalate resin or a thermoplastic resin, that is, polyethylene resin, Reinforce with polypropylene resin, polycarbonate resin, nylon, ABS resin, etc. to suppress deformation.

As a method of forming a resin on the outside of the thin metal core, for thermosetting resin and photocurable resin, dipping, spraying, brush coating, etc. are used. At the time of curing, heat curing or light irradiation curing is performed while rotating sideways. For the thermoplastic resin, a method may be used in which a thin metal liner is inserted into a split mold coated with a release agent, a gap is provided between the liner and the split mold, the resin is injected into the gap, and the resin is removed after curing.

The method of forming the resin inside the thin metal core is a thermosetting resin, in which the resin is filled inside and the excess resin is discharged when applied to the entire inner surface.
A method of inserting a spray and spraying the inside is used. At the time of heat-curing, it is turned sideways and heat-cured while rotating. In the case of a thermoplastic resin, the thermoplastic resin is inserted from the mouthpiece portion of a thin metal liner and blow-molded, or powder is put and heated while rotating to melt and fix the resin to form the entire inside of the liner. That is, in the fiber-reinforced pressure vessel of the present invention, a resin-impregnated fiber is wound around a composite liner in which a thin metal core is reinforced by a resin, is wound by a filament winding method, and is cured by a treatment. The types of fibers that can be used include glass fibers, carbon fibers, and Kevlar. The fibers to be wound are bundles and do not mean one fiber.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described based on examples with reference to the drawings. FIG. 1 is a cross-sectional view of a fiber reinforced pressure vessel according to an embodiment of the present invention, in which a composite liner has a reinforcing synthetic resin 2 formed on the outer side of a metal core 1, and a composite liner is formed on the composite liner. The fibers 3 and 4 impregnated with the resin are wound and reinforced. Metal core 1 is body 1
1 and the dome portions 12 at both ends thereof, each dome portion 12 is provided with a boss portion, one is a base portion 13 for introducing gas, and the other is a blind boss portion 14. . The resin-impregnated fiber is first wound by the filament winding method and then by the helical winding layer 3.
The body 11 and the dome 12 are reinforced, and then the hoop winding layer 4
This strengthens the body 11 in the circumferential direction. The helical winding is formed thicker in the dome portion 12 than in the body portion 11. The composite liner after winding the fibers is cured while being heated or irradiated with light while rotating so that the resin is not biased.

FIG. 2 is a cross-sectional view of a fiber reinforced pressure vessel according to another embodiment of the present invention. The composite liner has a metal core 1 and a reinforcing resin 2 formed inside. In this case, the helical winding layer 3 and the hoop winding layer 4 of resin-impregnated fibers are directly formed on the metal core 1 of the composite liner by the filament winding method. However, when unevenness is generated on the metal core surface of the liner, the resin is also coated on the outside of the core to smooth the surface.

Next, a method for producing a thin metal part for the liner core will be described with reference to the drawings. 3 and 4 are explanatory views showing a method for producing a dome portion and a body portion with a press die by a hot working method. FIG. 3 shows the semi-molten metal 7 pushed by the press 6 in the die 5, before the semi-molten metal is deformed, and FIG. 4 shows the state after the deformation. According to this method, the dome portion 12 and the boss portion 14 can be integrally molded. At this time, a hole is formed in the boss portion 14 by drilling and screw hole processing is performed to form a die. Further, if the die 5 is provided with a projection corresponding to a hole of the die, it is possible to manufacture the die by screwing without the need for drilling. Body 1
The length of 1 can be long or short. The strength of the dome portion can be increased by forming the dome portion so that the thickness increases from the body portion to the apex.

5 and 6 are explanatory views showing a method of forming a dome portion by a cold working method. FIG. 5 shows a state in which the metal plate 8 is deformed by plastic working by the die 5 and the press 6, and FIG. 6 shows a deformed state. In this method, the dome portion 12 is provided with the flange portion 15 extending to the body portion. Also, with this method, the bosses cannot be molded at the same time, so it is necessary to separately manufacture and bond them. The base is welded by making a hole at the top of the dome, and the blind boss is welded without making a hole at the top of the dome.

Further, only the body portion of the metal core is produced by a method such as drawing a tube, extruding molten metal, or drawing, or by roll-forming a thin metal plate and seam welding the joint portion. Can be done. By the way, seam welding is possible with 0.05 mm or more. Alternatively, a method may be used in which a thin metal plate is roll-molded for the body portion, a flange is provided in the joint portion, the flange portion is caulked, and the caulked portion is seam welded. The dome portion may be separately manufactured and welded, or only one of the dome portions may be manufactured by drawing.

Next, a method for assembling and joining the body portion of the core of the liner and the dome portion will be described with reference to the drawings. The first is a method of inserting the other into either the body or the dome and welding them. FIG. 7 is a sectional view when the flange portion of the dome portion 12 is inserted into the opening portion of the body portion 11 and the gap between the two is welded or silver brazed, and FIG. 8 is the dome portion 12 in the opening portion of the body portion 11. FIG. 4 is a cross-sectional view showing a case where the flange portion of the above is covered and the gap between the two is welded or silver brazed. The inner diameter of the body 11 to the dome 12
There are three methods for making the diameter larger than the outer diameter. The first method is to make the inner diameter of the body 11 larger than the outer diameter of the dome 12. The second is to heat and spread the body 11,
This is a method of cooling the body after inserting the dome portion 12. The third method is to expand the opening of the body 11 by plastic working so that the opening is larger than the outer diameter of the dome 12. Conversely, the method of making the inner diameter of the dome portion 12 larger than the inner diameter of the body portion 11 is also the same. This method comprises a step of covering the body portion 11 or the dome portion 12 with the other, and then a step of welding the gap between the two by welding or silver wax. A groove may be formed in the place where the body portion 11 and the dome portion 12 overlap by drawing. By doing so, it is possible to reinforce even if the welding has no strength. Incidentally, the unevenness caused by covering one of the body portion and the dome portion on the other, and the unevenness due to the groove are covered with the synthetic resin in the present invention, so the surface becomes smooth,
There is no unevenness or cavities when winding the fibers.

FIG. 9 is a cross-sectional view showing the second assembly and joining method. The step of inserting the dome portion 12 deeply into the opening of the body portion 11, the step of joining the gap between the two by welding or silver wax, and then The process includes bending the protruding portion 111 of the body portion along the dome portion 15 by drawing. In this way, by protruding the opening of the trunk and bending it,
When internal pressure is applied, it is possible to reduce the load of shear stress applied to the joint portion between the body portion and the dome portion. An internal force is applied to the bent portion due to the internal pressure, which can be suppressed by wrapping the fiber on the outside. The unevenness of the body portion due to the insertion of the dome portion 12 into the body portion 11 and the unevenness due to the bending of the protruding portion 111 of the body along the dome 12 are smooth because the reinforcing synthetic resin is covered in the present invention. , There are no cavities when the fiber is wound, and the fiber does not slip and become uneven. The effect of joining the body portion 11 and the dome portion 12 does not change even after the protruding portion is bent. Note that, in FIG. 9, the dome portions are inserted at both ends of the body portion, but naturally the effect is the same even if only one of them is provided.

FIG. 10 is a sectional view showing a third assembling and joining method. Step of inserting the ring-shaped contact plate 16 inwardly in the opening of the body 11 and joining the gap between the body 11 and the contact plate 16 by welding or silver wax, cover the flange of the dome 12 with the contact plate 16. , The process of joining. A groove may be formed in the place where the contact plate 16 and the body portion 11 or the dome portion 12 overlap by drawing. By doing so, it is possible to reinforce even if the welding has no strength. Even if there is a groove, the cavity of the groove does not cause a problem when winding the fiber, because in the present invention, the fiber is wound after being coated with the resin.

When the rigidity is insufficient, a plurality of rings made of the same metal as the core may be provided so as to circumscribe the core. After that, the resin is filled until it exceeds the thickness of the ring to be circumscribed so that the surface around which the fiber is wound has a smooth surface without unevenness. The cross section of the ring may be rectangular, circular, or tubular, but the thickness or diameter is preferably 2 mm or less.

Further, as a method for increasing the rigidity, a method of forming a groove in the body portion of a thin metal in the circumferential direction by a drawing method can be considered. The groove is filled with a reinforcing resin to make the surface smooth.

[0025]

Since the present invention is configured as described above, it has the following effects.

Since the core made of a thin metal and the composite liner made of a synthetic resin for reinforcing the core are used as the liner, a lightweight, high-grade fiber-reinforced pressure vessel having no gas permeability can be manufactured.

Since the thin metal core is reinforced with resin,
Even when filament winding is performed, there is little deformation, and the fiber can be wound while preventing slippage.

By forming the synthetic resin on the outside of the thin metal core, the irregularities formed on the outside of the core are smoothed, and the resin-impregnated fiber can be wound evenly.

Since the core of the liner is manufactured by dividing it into parts, it is easy to manufacture, and since the joining is made robust, the reliability is high and it is possible to cope with the diversification of the dimensions of the liner.

[0030]

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a fiber reinforced pressure vessel.

FIG. 2 is a sectional view showing another embodiment of the fiber reinforced pressure vessel.

FIG. 3 is an explanatory view showing a method of manufacturing a body portion and a dome portion of a liner core by a hot working method.

FIG. 4 is an explanatory view showing a method of manufacturing a body portion and a dome portion of a liner core by a hot working method.

FIG. 5 is an explanatory view showing a method of manufacturing a body portion and a dome portion of a liner core by a cold working method.

FIG. 6 is an explanatory view showing a method of manufacturing the body portion and the dome portion of the liner core by a cold working method.

FIG. 7 is a cross-sectional view showing an embodiment in which a body portion and a dome portion are assembled and joined.

FIG. 8 is a cross-sectional view showing an embodiment in which a body portion and a dome portion are assembled and joined together.

FIG. 9 is a cross-sectional view showing another embodiment of assembling and joining the body portion and the dome portion.

FIG. 10 is a cross-sectional view showing another embodiment of assembling and joining the body portion and the dome portion.

[Explanation of symbols]

1 core 2 synthetic resin 3 Helical winding layer 4 hoop winding layers 5 mold 6 Press type 7 General-purpose male metal 8 metal plates 11 torso 12 Dome part 13 Base 14 Blind boss 15 Flange 16 Patch 111 protrusion

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F16J 12/00 B29K 105: 08 // B29K 101: 10 105: 22 105: 08 B29L 22:00 105: 22 B29C 67/14 C B29L 22:00 67/18 F term (reference) 3E072 AA01 CA01 CA03 CA10 3J046 BA02 BB02 BC13 BD09 CA02 CA04 DA05 EA02 4F205 AA04 AA11 AA13 AA28 AA29 AA36 AA39 AA41 AD03 AD16 H33 HA40 HA02 HA40 HA02 HA40 HA02 HL12 HL13 4F213 AA36 AD16 AG03 AG07 WA14 WA32 WA40 WA53 WA87 WB01 WB11 WB22 WB28 WE16 WF01 WF06 WF27 WK03 WW06 WW15 WW33

Claims (4)

[Claims] 1. A liner having a body portion and dome portions bounding both ends thereof, each dome portion being provided with a boss portion, and at least one boss portion of the dome portion serving as a mouthpiece capable of introducing gas is provided with a resin. In a pressure vessel for winding and strengthening impregnated fibers, the liner is a composite liner consisting of a thin metal core and a reinforcing synthetic resin formed on the outer surface or inner surface thereof, and the thin metal core At least the thickness of the body is 0.5 mm to 0.05 mm
The fiber-reinforced pressure vessel and the method for producing the same, wherein the body portion and at least one dome portion are separately manufactured, assembled, and joined. 2. A method of separately manufacturing and assembling a body portion and a dome portion of a thin-walled metal core of a liner by covering either the body portion opening portion or the dome portion flange portion with the other. The method for producing a fiber-reinforced pressure vessel according to claim 1, comprising a step of joining a gap between the body portion and the dome portion. 3. A method of separately manufacturing and assembling a body portion and a dome portion of a thin-walled metal core of a liner, the step of deeply inserting the dome portion of the core into an opening portion of the body portion, 2. The method for manufacturing a fiber reinforced pressure vessel according to claim 1, comprising a step of joining a gap between the dome portion and the body portion, and a step of bending the protruding portion of the body portion by drawing along the dome portion. 4. A method of separately manufacturing and assembling a body portion and a dome portion of a thin-walled metal core of a liner by inserting a ring-shaped contact plate inscribed in an opening of the body portion. 2. The method for manufacturing a fiber reinforced pressure vessel according to claim 1, further comprising the step of joining the back plate and the body to each other, and the step of covering the back plate with the flange of the dome portion to join the back plate and the dome portion. .